Here we have the mystery of this vision explained. The apostle wonders at the sight of this woman: the angel undertakes to open this vision to him, it being the key of the former visions; and he tells the apostle what was meant by the beast on which the woman sat; but it is so explained as still to need further explanation. 1. This beast was, and is not, and yet is; that is, it was a seat of idolatry and persecution; and is not, that is, not in the ancient form, which was pagan; and yet it is, it is truly the seat of idolatry and tyranny, though of another sort and form. It ascends out of the bottomless pit (idolatry and cruelty are the issue and product of hell), and it shall return thither and go into perdition. 2. This beast has seven heads, which have a double signification. (1.) Seven mountains - the seven hills on which Rome stands; and (2.) Seven kings - seven sorts of government. Rome was governed by kings, consuls, tribunes, decemviri, dictators, emperors who were pagan, and emperors who were Christian. Five of these were extinct when this prophecy was written; one was then in being, that is, the pagan emperor; and the other, that is, the Christian emperor, was yet to come, Rev 17:10. This beast, the papacy, makes an eighth governor, and sets up idolatry again. 3. This beast had ten horns; which are said to be ten kings which have as yet received no kingdoms; as yet, that is, as some, shall not rise up till the Roman empire be broken in pieces; or, as others, shall not rise up till near the end of antichrist's reign, and so shall reign but as it were one hour with her, but shall for that time be very unanimous and very zealous in that interest, and entirely devoted to it, divesting themselves of their prerogatives and revenues (things so dear to princes), out of an unaccountable fondness for the papacy.